From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261185AbVDYVA0 (ORCPT ); Mon, 25 Apr 2005 17:00:26 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261188AbVDYVA0 (ORCPT ); Mon, 25 Apr 2005 17:00:26 -0400 Received: from pentafluge.infradead.org ([213.146.154.40]:6308 "EHLO pentafluge.infradead.org") by vger.kernel.org with ESMTP id S261185AbVDYVAW (ORCPT ); Mon, 25 Apr 2005 17:00:22 -0400 Subject: Re: [PATCH 5/7] dlm: device interface From: Arjan van de Ven To: David Teigland Cc: linux-kernel@vger.kernel.org, akpm@osdl.org In-Reply-To: <20050425151303.GF6826@redhat.com> References: <20050425151303.GF6826@redhat.com> Content-Type: text/plain Date: Mon, 25 Apr 2005 23:00:18 +0200 Message-Id: <1114462819.8442.57.camel@laptopd505.fenrus.org> Mime-Version: 1.0 X-Mailer: Evolution 2.0.4 (2.0.4-2) Content-Transfer-Encoding: 7bit X-Spam-Score: 3.7 (+++) X-Spam-Report: SpamAssassin version 2.63 on pentafluge.infradead.org summary: Content analysis details: (3.7 points, 5.0 required) pts rule name description ---- ---------------------- -------------------------------------------------- 1.1 RCVD_IN_DSBL RBL: Received via a relay in list.dsbl.org [] 2.5 RCVD_IN_DYNABLOCK RBL: Sent directly from dynamic IP address [80.57.133.107 listed in dnsbl.sorbs.net] 0.1 RCVD_IN_SORBS RBL: SORBS: sender is listed in SORBS [80.57.133.107 listed in dnsbl.sorbs.net] X-SRS-Rewrite: SMTP reverse-path rewritten from by pentafluge.infradead.org See http://www.infradead.org/rpr.html Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org > +static struct rw_semaphore lockinfo_lock; why are you using a rwsem here? rw semaphores are *expensive*. Really expensive. Might well not be worth it unless you expect really frequent readers compared to writers *and* long hold times. Can you give an idea about how frequent the reader case is? (and if it's really frequent, wouldn't RCU be a better solution?)